Chris Sutton in disbelief at 'incredible' Rangers footage he's now seen
Bojan Miovski scored the winning goal in the 91st minute of the contest at Ibrox after being introduced from the bench.
Derek McInnes accepted after the game his side are still not playing anywhere near their best.
Yet Rangers have still won four on the spin in the Scottish Premiership to move into second place, five points behind leaders Celtic.
St Mirren had their moments against Rangers and could easily have gone ahead in the second half.
And the visitors were also denied a strong penalty appeal in the first half, which thankfully went in the Gers' favour.
Chris Sutton's big takeaway from Rangers vs St Mirren
St Mirren felt they should have been given a penalty when Emmanuel Fernandez caught the boot of Ismeal Kabia inside the box.
Kabia was too quick for Fernandez and the Rangers centre-back was far too rash with his challenge.
However, referee Don Robertson - who was well positioned - did not point to the spot and VAR did not intervene.
That suggested they did not feel it was a clear and obvious error from Robertson.
Chris Sutton could not disagree more, though, judging by what he posted on his personal X account on Thursday morning.
"Just watching the St Mirren highlights," he posted. "How St Mirren weren’t awarded a penalty is incredible."
Sutton's opinion is backed by many, but what do the laws say?
Bobby Madden clarifies laws around St Mirren penalty shout
Interestingly, St Mirren's players did not make too much of the challenge on Kabia.
This is likely because he managed to get the pass away before the challenge was made.
Former referee Bobby Madden has also weighed in on the subject in a video posted via Instagram.
"You can see the attacker plays the ball away from the defender, who comes in late and steps on the foot of the attacker," he said.
"We need to consider what UEFA's new platform Clear Lines says about such situations.
"A direct free-kick is awarded if a player shows a lack of consideration, careless or a disregard for his opponent. Reckless.
"Clear Lines states that there should be a penalty awarded or VAR intervention if the step on foot is clear, a significant degree of intensity or it impacts on the attacker."
Rangers got away with one in their win over St Mirren, then, but the bad decisions will likely far outweigh those in the Gers' favour over the season.